The invention relates to polymer foams. In particular, the invention relates to polymer foams having low densities with enhanced physical properties.
Foam structures are useful in the areas of packaging, athletics, water sports, and construction. In general, the foams are low density polymeric materials with good physical properties that are capable of supporting loads without adverse deformation. In general, the physical properties required by these applications suggest the use of high density foams. It is generally required that the foams have good proportional limit, compressive properties, shear properties, fatigue properties, and buckling limits, as defined, for example, in "Machinery's Handbook," E. Oberg, et al., Green, Ed., Industrial Press Inc., New York, 1992, pages 166, 168 and 253.
Physically-blown foams, particularly foams with enhanced physical properties are useful, for example, in packaging, automotive, construction, contact sports, water sports, exercise, and appliance applications. It is important to maintain good foam properties (e.g., cushioning and resistance to creasing) at low foam densities.